| 摘要 |
PROBLEM TO BE SOLVED: To provide an FM modulator by which FM modulation is conducted for eliminating a 2HD (secondary harmonic distortion of an FM signal obtained through modulation) produced on a transmission path to the FM demodulator, thereby reducing a noise level after FM demodulation. SOLUTION: A branch section 102 branches an electric signal outputted from a signal source 101 into two. An FM modulation section 103 has the function of converting the amplitude change of an input signal into a frequency change in an output signal and converts 1st and 2nd electric signals obtained by branching operation at the branch section 102 into FM signals respectively. In this case, the FM modulation section 103 converts the 1st and 2nd electric signals into two FM modulation signals, in a way such that a 2HD produced by one FM signal and a 2DH by the other FM signal are mutually cancelled on a transmission path toward an FM demodulator. |
